1. Field of the Invention
The present invention relates to an inside rose liner for a lock. In particular, the present invention relates to a lock with improved torque-resistant capacity.
2. Description of the Related Art
A typical door lock includes a main body having an inside seat and an outside seat, an inside rose liner securely mounted to the inside seat, an outside rose liner securely mounted to the outside seat, an inside rose, an outside rose, an inside handle, and an outside handle. The inside handle and the outside handle of lever type are convenient to the disabled. The inside seat includes two diametrically disposed grooves, and the inside rose liner includes two diametrically disposed protrusions respectively engaged in the grooves of the inside seat. Similar design is adopted in the outside seat and the outside rose liner. The door lock of such a structure is simple and has a low manufacture cost. Nevertheless, the torque resulting from the force applied to the lever type handle for opening the door is relatively greater than that of a knob type handle. The simple engagement of the grooves and protrusions between the respective rose liner and the respective seat is insufficient to resist the torque if lever type handles are used. As a result, the inner parts of the door lock using lever type handles are apt to be damaged.
U.S. Pat. No. 6,364,383 discloses an easy-to-install door lock with burglar-proof effect for the outside rose assembly, wherein each of the inside seat and the outside seat of the main body of the door lock includes two diametrically disposed flat surfaces. Further, the inside rose liner includes a threaded inner periphery for threadedly engaging with an outer threading of the inside seat. An anti-torque ring is engaged on the outside seat for improving the torque-bearing capacity. The anti-torque ring includes a central hole having two diametrically disposed flat sections, allowing the anti-torque ring to be mounted around the outside seat without the risk of relative rotation and providing improved burglar-proof effect. An adjusting sleeve is threadedly engaged with the outside seat, with an end of the adjusting sleeve being securely engaged with a central stepped portion of the outside rose, and with the other end of the adjusting sleeve abutting against the anti-torque ring to thereby retain the anti-torque ring in place.
However, the adjusting sleeve of the door lock disclosed in U.S. Pat. No. 6,364,383 has to be cylindrical, and the outside rose must be processed to form the central stepped portion for receiving the end of the cylindrical adjusting sleeve. The design flexibility of the outside rose is limited. Further, it is difficult to provide the cylindrical adjusting sleeve with high strength. Thus, the strength of the whole lock structure is limited.